Grisly news for grizzly bears

On public television’s “Nature”, broadcast Sunday night, a Yellowstone National Park grizzly bear was filmed shaking loose fatty cones from a white bark pine tree as a meal just before going into hibernation.

The U.S. Fish and Wildlife Service reported on Monday that white-bark pines, a tree found at high elevations through much of North America, face “imminent” risk of extinction brought on by climate change.

“At the end of the century, less than 3 percent of currently suitable habitat is expected to remain,” the FWS said in its finding. The agency was responding to a petition by the Natural Resources Defense Council to put white bar pines on the federal endangered species list.

Masses of grey (dead) and red (dying) white bark pines can be seen by visitors on slopes of Yellowstone’s Mt. Washburn, probably the best place in the park for viewing grizzlies.

Death of the pines is grisly news for the 500 to 700 grizzly bears that inhabit America’s first (and most famous) national park and its surrounding Greater Yellowstone Ecosystem.

White bark seedpods “are arguably the most important fattening food available to grizzly bears during late summer and fall,” the federal government’s Interagency Grizzly Bear Task Force concluded a few years ago.

“Will today’s cubs, if they live 20 years, still have this food source?” asked Dr. Steven Running, a University of Montana ecology professor.

No, according to Monday’s finding. The pines face voracious insects and invasive disease that previously had been unable to thrive in the white barks cold, high habitat.

Climate change has allowed pine bark beetles to regularly reach the high-elevation pines, where the trees have not evolved defenses. Rapid warming has limited lengthy sub-zero cold snaps that used to limit beetle reproduction and movement upwards to ridge lines where the tree is found.

“Anyone who doesn’t believe in climate change can look at this decision and the reams of scientific research behind it: The masses of grey and red trees that littler the forests above my home in Montana are a testament to the damage already being wreaked on our high-elevation ecosystems,” said Louisa Willcox of the Natural Resources Defense Council.

Grizzly bears in British Columbia scoop salmon out of streams. Berries supply much of the bears’ diet in the Northern Rockies. In Yellowstone, however, the white bark pine is essential — especially for female grizzlies.

The Fish and Wildlife Service gave what it calls a “warranted but precluded” decision on the fast-dying white bark pines.

It acknowledges that climate change is driving the species to extinction, but the Service’s limited budget prevents adding white bark to the endangered species list at this time.

A recent study found 80 percent of the white bark pine forests in the Greater Yellowstone Ecosystem are dead or dying. The pines are also found in the high Sierras, and north through the Cascades into British Columbia.

The Service will review the pines’ status in a year to determine if money is available to begin a recovery plan. But money to manage the Endangered Species Act faces deep cuts in Congress.